The present invention relates generally to virtual image display optical systems, and more particularly, to a wide spectral bandwidth virtual image display optical system as a display monitor for computer applications.
Conventional display systems such as CRT monitors or LCD panels are direct-view systems in which the users view a display image on the monitor surface. For a large screen size, the display is correspondingly larger in size. As a result, the conventional CRT monitors are not only costly, but are also bulky and heavy.
Prior art related to the present invention include U.S. Pat. No. 4,294,515 issued to Kaufman and U.S. Pat. No. 3,940,104 issued to Withrington. The Kaufman patent teaches a virtual image system using spherical mirrors. This approach is typically useful for a display system with small field-of-view (small display screen size). The Withrington patent teaches an optical system that is used in a transmissive configuration for head-up display applications with image distance at infinity. The system typically includes one aspherical optical mirror surface for displaying a monochrome image.